Marine propulsion unit



y 2 19-59 R. M. UPTON arm. 2,85,446v

I MARINE PROPULSION UNIT,

Filed May 24, 1954 4 Sheets-Sheet i I July 21, 1959 r v R. M. UPTON ET AL 2,395,446

' MARiNE PROPULSION UNIT Filed May 24, 1954 4 Sheets-Sheet 2 IN VEN TORJ' I o m E cmvezes oguauas rA/v morn-A1 B- July 21, 1959 R. M. UPTON ETAL 2,895,445

' MARINE PROPULSION UNIT Filed-"W2 4; 1954 4 sheet -sheet 5 a; v 9 J2 .7 #9 za 9 1/0 Ila .779 0/ A? Jul-y- 21, 1959 R. M. UPTON I ETAL 2,895,446 MARINE PROPULSION UNIT 4 Sheets-Sheet 4 Filed May 24, 1954 v 000644: V/M P4775 BY nited States Patent MARINE PROPULSION UNIT Ralph M. Upton, Detroit, and Charles Douglas Van Patten, Flint, Mich.

Application May 24, 1954, Serial No. 431,666 3 Claims. (Cl. 115-34) This invention relates generally to a marine propulsion unit, the term propulsion unit being used to denote an assembly which includes, as essential components, a power plant or engine, a propeller and shaft, and driving means between the engine and propeller shaft, which means may include a device such as a gear reduction box. The invention provides an improved construction for mounting the essential propelling components and accessories as a complete, integrated assembly which can'be quickly installed in and removed from an improved hull structure as a unit.

According to the invention, a frame structure is provided, and the various componentsof the propulsion unit are all mounted in and supported by this frame, which encases the lower portions of the components, except for the propeller shaft and propeller which are located below the bottom of the frame, but within the area thereof in plan. The bottom of the hull of a .vessel in which the unit is to be used is constructed with an opening dimensioned to receive the lower portion of the frame, and the opening is surrounded by a well having sides extending above the normal load water line of the hull and open at the top, so that the entire propulsion unit can be assembled in the hull or removed therefrom for initial installation, replacement, or major overhaul, without the necessity of having to remove the hull from the water. All that required for removal is to disconnect the frame structure from the hull and lift the entire propulsion unit out, allowing the well to fill with water.

The invention is particularly directed to the problem of installing and replacing marine propulsion units of relatively large power output, and is especially adapted to meet the requirement for power plants of this type in armed service where conditions are often encountered requiring the replacement of a power plant in as short a time as possible.

Preferably the propulsion unit of the invention incorporates all major accessories for power plant'operation, such as reservoirs for-lubricant andcoolant, major controls, and heat exchange units required for maintainingproper operating temperatures of the engine. The

frame structure is constructed to mount allsuch acces--- sories.

Fortemperature control, the frame of the propulsion unit includes a compartment or section which will be; termeda sea chest, preferably located along the bottom portion of the frame, bulk-headed therefrom, and provided means for circulating sea water through heat exchange units mounted in the sea chest, one unit being connected in the circulation system for each fluid, such as coolant, or lubricant, required for power plant operation.

Effective means are also providedfor mounting the propulsionunitin the well ,providedin the hull, and.

sealing the unit in the well so thatdeakage will, not de- 9 velop under operating conditions, even the severe operatlar 'fiuid. These circulation systems have not been shown, as their details are well known and form no part ofthe present invention. Provision is made for circu-" Patented July 21, 1959 ICE ing conditions that are encountered with high-powered some of the components of which, such as the engine,-

gear box, etc., are shown in phantom due to the fact that the exact nature of the equipment will vary from one craft to another;

Fig. 2, an end elevation of including adjacent portions of the well structure provided in the hull;

Fig. 3, a transverse section of the lower portion of the unit taken along the line 33 of Fig. l and including mounted on a common frame. v

lustrated, this frame is designated generally by the reference 10, and is made as a large boxlike structure seals employed between the hull and propulsion unit;

Fig. 4, a sectional elevation of the propulsion unit taken as'indicated by the line 4-4 of Fig. l, but including structural elements of a representative hull construction for a twin-screw craft powered by a pair of propulsion units of the invention. This construction of the hull will be symmetrical about the longitudinal center line thereof,

and, therefore, only half is shown in this view. For the sake of clarity, the frame structure only of the propulsion unit is shown in this view. Although this particular section shown in Fig. 4 shows a twin-screw installation,

this device may be used in single or multiple (any number) screw installations;

Fig. 5, a plan view of the lower portion of the frame structure of the propulsion unit, this portion being hereinafter referred to as a sea chest; and r Fig. 6, a sectional elevation of the structure shown in Fig. 5. i

All the various components of the propulsion unit are In the construction ilopen at the top and having side, end, and bottom walls. The components carried in this frame, referring to .Fig. 1, include an engine 11 driving a propeller shaft 12,

and propeller 13a journaled in a contra-propeller strut 13, through a reverse gear 14 and a V-drive type of gearbox 15. A propeller 13a is mounted on the shaft 12. Also carried by the frame is an engine oil reservoir 16, a gear box oil reservoir 17, and an engine coolant reservoir 18 mounted above the level of the engine on an open framework generally designated 19. Engine room con framework 19 in a controls 20 are also carried by the venient location.

Part of the bottom portion of the frame structureconsists of a separate unit, termed asea chest, and generally designated by the reference 22. This unit, which is detachably secured to the lower portion of the frame structure, is shown in detail in Figs. 5 and6 and contains suitable heat exchangers for regulating the tempera ture of engine coolant, engine oil and gear box oiln Such fluids will be generally referred to as operatin g' fluids. Each heat exchanger in the sea chest 22 is suitably connected in the circulation system for a particulating sea water through the sea chest, in contact with the heat exchangers.

the unit looking aft, with parts of the frame structure being shown in section, and.

This sea chest construction will be igflater described .morecompletely. 1 l 1;

From the foregoing description of the propulsion unit 3 generallypit canbe seenithat the frame structure providesa. support forall. components. .necessary..to. propel a vessel with the exception of fuel for the engine 11.

The over-all construction can perhaps be more clearly understood from an explanation of the manner in which a propulsionunit of this type'may. be mounted in: a vessel. A representative vessel construction-is given in Fig.4, showinga section through onehalf ofthe'hull-ofa a vessel provided--with-twin propulsion units of. the, present type.

The bottom 25of thehull isprovided with an opening 26,

whichinplan'corresponds in shape. to the planxview-of the sea .chest- 22, shownin Fig. 5. This opening is defined longitudinally by. a large structural-member 28,-.termed a log, which is carried between two transverse. engine bed' members 29 and 3tl, respectively. Inner and outer longitudinal engine: bed members. 31 and 32 are supported. by the log and ribs. These longitudinal'engineabed memberspass'through the fore and. aft :engine room bulkheads thus forming an enclosed water-tight well of rectangular configuration which surrounds the bottom openingl'26 andextends. upwardlya distanceabove the normal load water line 34 of the vessel.

The engine frame unit 10 is formed with a laterally extending flange 36 projecting outwardly aroundits upper edge. This flange 36 engagesthe top surface of the longitudinal engine bed:members to support the propulsion unit in the hull, and suitable screws. 38 are employedfor connecting the frame unit 10 to the engine bed members. When the frame unit 10 is so installed, the sea chest portion 22 thereof projects downwardly through. the hole 26 inthe bottom of the vessel, and the various parts of the construction are dimensioned so that the bottom of the sea chest lies substantially flush with the bottom of the hull. Preferably, the vessel is constructed so that the upper structure immediately above the engine room, be

it deck, or cabin roof 40 as illustrated, is removable. When this roof 4!) is removed and the screws 38 are removed to disconnect the frame unit 10 from the engine bed, the entire propulsion unit can be lifted from the hull without having to dry dock'or beach the vessel. Sea water will not rise above the level of the load water line 34 in the well formed by. the engine bed members.

With this over-all picture of the propulsion unit. in mind, a more detailed description will now be givenof the construction of the frame structure 10 and the-sea.

chest portion-22 thereof. It should be recognized that the propelling components, such as the engine 11, reverse gear 14, V-drive 15, and the various reservoirs for. lubricants and coolant are individually standard commercial items. dividual components according to the size or output'ofa particular propulsion unit and the requirements of the components thereof individually, especially with respect to cooling and lubricating systems. The essential .characteristic. of the frame structure, in so far as the present invention. is concerned, is that it must have length. and width dimensions sufficient for mounting all the various propelling components. The length and width: dimensions of the bottom portion of the frame are also related to the installation .of the propeller shaft 12 and to the diameter of the propeller. 13a and width of thecontrapropellerstrut 13. v

. In-other. words, the area of this portion of the frame, in-plan, must include these elements; and, therefore,wthe length of the frame must be suflicient to provide: a proper mounting angle for the propeller shaft 12, and thewidth of the frame must be greater than the. .transverseqdimension of the strut 13 and propeller. 13a. 7

The frame 10 is a boxlike structure, open. attheutop,

and enclosed by starboard and portsidewalls 42 and.43,;

foreand aft end walls 44 and 45, and a bottom 1wall:46.

The depthof this boxlike structure-is suflicient-to-encase the various components of the. propulsionnnit belowfza level, ldefinedby the flange 36 at the top' of the .sidesand There: will be variation in any or all of the in;

Access panels 48 are shown as vprovidedin the starboard side wall 42. Other access-panels, such as the panel 49 (Fig. 2) are provided in the port side wall 43.

It is desirable that the dimensions of the opening 26 required in the hull structures be held as small as possible. The minimum limits of these dimensions are defined by the propeller shaft 12 and'itsangle of installation, and by the transverse dimensionof the strut13- or propeller 13a. According to the invention the opening 26 is filled by the bottom or sea chest'portion22 of the framet10, and with an inclined propeller shaft installation as shown, a T-sha-ped opening results with'the cross of the T overlying the propeller. Referring to Fig.5, the corresponding outline of the sea chest can be seen-in plan. Since the sea chest 22 is preferably made as a separate unit, an opening of similar shape is formed in the bottom wall 46 of the frame 10.

Thisopening-is. bordered by a flangei52 (Figs. 2 and 3) and the sides. 42 and 43 of the frame 10 are eachgiven a. generalainclination. downwardly from the upperflange 36 to join thislower flange 52, with suitable modifications. in thisinelined contour to provide bosses such as the boss 53 for mounting the access panels 49,. Thus, towards the forward section. of the frame 10, the sides 42 and 43 converge downwardly at quite a pronounced angle; whereas, towards the rear-end of the frame the sides 42 and 43 are closer to. the; perpendicular orvertical to mate withithe enlarged aft portion 54 (Fig. 5) of the sea chest 22.

Supporting brackets or mounts have not been shown for all thepropelling components carried by the. frame structure, .as the provision of suitable-elements of this kind is considered-to be'a matter :of design. The sea chest structure illustrated in Figs. Sand 6 is of sheet metal construction and is a T-shaped chamber with a boxlike aft portion 54 and a'relatively long, narrow forward portion 55. The top of this chamber is formed by a panel 60, T-shaped in plan (Fig. 5) which extends beyond the sides and ends. A downturned flange 61 is provided all along the edge of the panel 60, for a purpose to be presently described. The narrow forward section -of the structure is defined by an inclined forward end panel 62, side panels 63 and 64, and a bottom panel 65, formed with a depression 66 at its forward end, to provide a scoop-like overlap exists. The side panels 63 and. 64 of the forward section 55 are notched to abut against the. forward end panel of the aft section-54 and the side panels 63 and 64 each have a short projection'73 (Fig. 5), which extends.

underneath the bottom panel 72 of the aft sectionand is connected thereto. These projections 73 of the side panels are connected by .a transverse. end plate 74, also connected to the bottom panelsof the forward and aft sections, to complete the enclosure. A hollow fin structure '75, made up of side panels 76 and 77 (Fig. 2), is secured to the bottom panel of the forward section 55.

Approximately midway of the length of the narrow A portion 55v of the structure there is locateda heat exchange unit 78 .mounted in the top panel 60. 'This particular unit is designed to control the temperature of the lubricant for the V-drive gear box 15 in the specific. construction shown. .Complete constructional details of the heat exchange unit 78 have not been included in the drawings, as they are'well known. As far as the present invention is concerned, it seems suflicient to explain that the internal construction of the heat exchanger 78willbe such as to afford one path of travel for the operating fluid whose temperature is to be controlled, and-another-path -of travel for the sea water which'is to actas the temperaends of the structure, above theicload water line": of thew ture eontrollingmeans.

ture between the forward and aft sections 55 and 56,.an

provided with an internal transverse baflie 79, which extends between the sides 63 and 64 from the rear Wall 80 of the heat exchange unit aft to join with the panel 68 which formsthe forward wall of the portion 54. A conduit section 81 is interposed between an opening 82 in the baflie 79, and an opening 83 in the bottom member 65, this conduit section forming a passageway between theupper section of the sea chest as defined by the internal baflie 79, and the open rear end 84of thefin 75.

Two more heat exchange units are located in the aft portion 54 of the sea chest. One of these units, designated 85, is for regulating the temperature of the engine oil, and the other unit 86 is for regulating the temperature of the engine coolant. The remaining structural details of the sea chest construction can pe'rhaps be best understood from an explanation of the manner in which sea water circulates therethrough. With the unit installed in a vessel, sea water enters the sea chest through the scoop opening 67 at the forward end thereof, and flows rearwardly around the propeller shaft 12 which extends through the sea chest. A sealing bushing (not shown) is provided at the upper shaft housing member 87. For high speed craft, a relief valve 89 will usually be provided near the forward end of the sea chest to relieve excess pressure that may be built up inside. At the heat exchange unit A portion of the water enters the heat exchange unit 78 through the opening 90, while another portion flows underneath the heat exchange unit through the passage at91. Sea water flows from the heat exchange unit 78 through the discharge tube 92 tube being provided with a valve 93 to regulate the rate of flow. The transverse baffle 79 extending across the sea chest forms upper and lower compartments therein rearwardly of the heat exchange unit 78, and the upper of these compartments 97 acts to serve as a sea water exit or return spillway, leading to the conduit section 81 and thence outwardly through the rear end of the fin. Water coming from the discharge tube 92 of the exchange unit 78 flows along this return spillway, as indicated by the arrows 94.

. Sea water by-passing the heat exchange unit 78 through the passage 91 goes to the rear portion 54 of the sea chest, flowing around the conduit section 81, and upwardly into the portion 54, as indicated by the arrow 95 in Fig. 6, through an opening 96 formed in the bottom panel 72 thereof, between the overlying forward end panel 68 of the aft portion 54 and the underlying end plate 74 of the narrow forward portion 55. An internal baflle member 98 extends across between the forward walls of the heat exchange units 85 and 86, and a discharge tube 99 extends forwardly from a hole in this baflle member 98 through the forward wall 68 of the portion 54. This conduit section 99 provides a path of circulation between the portion 54 of the sea chest and the return spillway 97 and is preferably provided with a flow control valve 100.

Sea water flowing upwardly as indicated by the arrow 95, through the opening 96 and into the aft portion 54 is diverted outwardly by the baffle 98 to each heat exchange unit 85 and 86. Water enters the units through suitable apertures 101 in the forward walls thereof. Exit openings 102 are provided in the rear walls of each heat exchange unit and allow the flow of water from each unit into the central return passage 103, which communicates with the discharge tube 99, and thence to the return path to the sea through the conduit 81 and out the rear end 84 of the fin 75.

In addition to the sea water flow control valves 93 and 100, the rate of cooling of operating fluids by the exchangers will also be separately regulated by such well-known devices as the thermostatic flow control valves 104 which are shown located at the connection of each 78, a division occurs in the path of flow.

at the end thereof, this operating fluid system to the respective exchanger thereof.

Sea water can be circulated through the sea chest by a suitable auxiliary pump (not shown) when the vessel is not in motion. A pump intake connection 105 is provided in the portion 54 of the sea chest, and a pump outlet connection 106 is provided to the discharge spillway 97 thereof. An auxiliary pump operating between these connections, with the valve 100 closed, will draw water in the intake scoop 67 of the sea chest and cause circulation through the heat exchange units 85 and 86 thereof in the manner previously described. Little circulation will result through the exchange unit 78, but this is not important because ordinarily the gear box 15 will not be in operation except when the vessel is in motion and, therefore, there will be no necessity for cooling the gear box lubricant.

It will be appreciated by those skilled in the art that, were the invention to be applied to a lesshighly refined power plant where the temperature of a lesser number of operating fluids required regulation, the construction of the sea chest could be modified and simplified considerably.

In Fig. 3 there is shown a preferred form of seal employed all around the perimeter of the hull opening 26 for establishing a make and break water-tight connection between the propulsion unit and the hull of the vessel. The construction of this preferred type of seal is related to the construction of the sea chest just described. The sealing members are permanently secured to the hull structure, and comprise a resilient inner sealing strip 110 and a resilient outer sealing strip 111. These strips are mounted in a seal carrier member 112, which is preferably an extruded section, including channel portions disposed at right angles for mounting the seals 110 and 111 and a downwardly extending tapering lip 114, which has a certain degree of flexibility.

Seal 110 is adapted to engage the downturned flange 61, which extends all around the edge of the upper panel 60 of the sea chest, and is provided with an upwardly extending lip 116 which curls into tight engagement with the inside surface of the flange 61 when the weight of the propulsion unit settles partially on the seal 110 and deforms it.

The seal 111 is provided with an outwardly extending lip the sea chest side members such as the panels 63 and 64 as shown in Fig. 3. This sealing contact between the member 111 and the sides of thesca chest is designed to occur below that of the line of contact between the seal 110 and the sea chest so as to form a spaceor chamber 119, portions of which lie alongside the return spillway97 of the sea chest. Vent holes in the sides of the return spillway 97 communicate with the space 119 betweentheinner and outer seals 110 and 111 when the propulsion unit is installed. A second series of vent holes 122 are provided along the sides 63 and 64 of the narrow portion 58 of the sea chest and communicate with the space between the outer seal 111 and the resilient metal lip 114.

Vent holes 120 allow any water that seeps past the outer seal 111 and into the space 119 to be discharged into the return spillway 97, and thence delivered back to the sea. Vent holes 122 have a dual functioning. They can act to drain water from the space between the outer metal lip 114 and the outer seal 111 into the sea chest, or they can act to allow water to escape from the sea chest if the pressure head becomes too great therein. The thin flexible metal lip 114 acts to prevent the impact pressure resulting from the pounding of a high speed planing hull in the sea from imposing damaging loads on the flexible seals 111 and 110. It is to be noted that all seals are disposed so that sealing contact is automatically maintained and created by the lowering of the propulsion unit into position. At the same time this sealing contact can be readily 118 which engages and is compressed by and against broken without damaging the seals by merely lifting the propulsion unit vertically.

All constructional details of the installation described are; designed to contributeto the over-all Object of the in-' vention of providing a marine propulsion unit whose components areintegrated into a single structure to the fullest possible extent. The result to be attained is a unit which can be assembled, tested and repaired out of the hull of a vessel, and which can be installed in or removed from the hull with a minimum number of operations. For example, the only such operations required With the construction described are the fastening of the unit frame to the engine bed supports, the connection of fuel and exhaust lines-to the engine, and the connection ofbridge controls (if employed). In case of trouble in service, either mechanical, or by damage to external components, such as propeller or sea chest, the entire unit can be quickly replaced-with a spare unit and repairs made under more favorable working conditions than in the engine room of a vessel.

Due to the lack of standardization of marine propulsion components and their installation, the constructional details given herein cannot be more than representative of the present inventions. It is felt that those skilled in this art will be able to adapt the principles: of .the construction to the design of other units, and to employthe invention as defined in the following claims.

We claim:

1. A construction for mounting marine propulsion components. including an engine, gear box; propeller shaft andpropeller as a removable unit in the hull. of a yessehcomprising a frame supporting said components; saidframe having side and end walls adapted to. surround theilower portions of said engine and gear box belowv the load .water line level of said hull, said frame having a bottom portion connected to said side and end walls and adapted to-mount saidpropeller shaft and propeller, said propeller shaft extending downwardly and rearwardly through saidbottom portion, and said propeller being located beneath and within the area of said bottom portion, said-hull being formed with an opening in the. bottom thereof dimensioned to receive said bottom portion of said frame, sealing-means located between said bottom portion and the-periphery of said hull opening, a water-tight well having side and end walls surrounding said opening and extendingto' a-level above the .water line ofsaid hull, means for detachablysecuring said frame to the structure 0f; said wall; the said bottom portion of said frame being'constructed'to form a'chamber separated from the upper'portionthereof, a seawater exit opening formed toward the aft 'endof said chamber, said sealing means including outer-and-inner sealing members adapted to contact the-surface of the-bottom'portion of said frame at spacedrpoints 'forming a peripheral space therebetween, and means :ventingsaid peripheral space tosaid chamber, whereby any water flowing propeller as a removable unit in the hull of a vessel,.com-

past the outer of said sealing memberscan pass through said vent meansinto said chamber and thence back tothe. seathrough the exit opening therein.

2. The construction set forth in claim- 1 further characterized by said chamber being providedwith a sea water inlet openingtowards the forward end thereof, thereby forming in conjunction with said exit opening a normal path of circulation for sea water through said chamber, a heat exchange unit located in said chamber in saidpath ofcirculation, and means for connecting said heat exchange unit through the upper wall of said chamber in the path of circulation of a propulsion component-operating fluid whose-temperature is to be controlled.

3. A construction for mountingman'nepropulsion components including an engine, gear box, propeller shaftand prising a frame supporting said components,- said; frame having side and end walls adapted to surround the lower portions of said engine and gear box below the load water line levelof said hull, said frame. having a bottom portion connected to said side and end walls and adaptedto mount said propeller shaft and propeller, said propeller shaftextending downwardly and rearwardly through said bottom portion, and said prop eller being located beneath and within-the area of said bottom portion,.said hull being formed with an opening in the bottom thereof. dimensioned to receive said bottom portion of said frame, sealing means located between said bottom portion and the periphery of said hull opening, a water-tight well having side and end walls. surrounding said opening and extending to alevel abovethe Water line of said hull, means for detachablysecuring said frame to the structure of saidwall, the said lower portion of said frame being constructedas asea water. chamber, having top, side and bottom Walls, said top wall projecting laterally beyond the side and end Walls thereof and being formed with a down-turned flange, said sealing means. comprising an inner sealing member carried by said hull around the periphery of the opening therein, said inner-sealing member adapted to be contacted by said downturned flange, an outer sealing member carried by said hull around the periphery of said opening and adapted to contact the sides and end surfaces of said bottom portion, and a flexible metallic sealing strip interposed between said hull and bottom portion exteriorly of said outer 3 sealing member.

References Cited in the file of this patent UNITED STATES PATENTS 1,542,165 Oechsle "June 16, 1925 1,754,983 Cumbo Apr. 15,, 1930 2,103,183 Rockwell 'Dec. 21, 1937 2,387,700 Cribb Oct.23, 1945 2,466,635 Brown Apr. 5, 1949 2,682,852 Ruffolo July 6, 1954 

